This application relates generally to connectors and, more particularly, to connectors sized to receive a threaded apparatus.
Aircraft engines typically include a plurality of threaded connections that are torqued during assembly. For example, an aircraft engine may be mounted to an aircraft at various locations, such as on a wing, to a fuselage, or to a tail. The engine is typically mounted at a forward and an aft end with a mounting system that includes a plurality of thrust links including connectors at each end. The connectors include openings extending therethrough that are defined by substantially planar inner surfaces including a plurality of threads.
The thrust link connectors are exposed to potential vibrational stresses that are induced during engine operation. To minimize the effect of exposure to such vibrational stresses, threaded components are torqued. When threaded components are loaded by torque or an external load, stresses are induced within the connectors. A highest stress area typically occurs in a first thread. More specifically, a highest stress is induced into a first thread root fillet that is defined between the first thread and a subsequent thread. Continued exposure to such stresses, may weaken the first thread and reduce a low cycle fatigue capability of the threaded connection. Prolonged reduced low cycle fatigue may shorten a useful life of the threaded connection.
To facilitate improving the low cycle fatigue capability of threaded connections, the threads of at least some known threaded components are rolled to provide a surface that is pre-stressed in compression. Such a process is time-consuming. In some other known applications, thread rolling is not available as the entire threadform is machined, and in these applications, a buttress threadform is fabricated from high strength super alloys and is used to facilitate improving low cycle fatigue capability. However, high strength super alloys are expensive and difficult to machine.
In an exemplary embodiment, a connector for receiving a threaded component reduces stresses induced from the threaded component into the connector. The connector includes a top side, a bottom side, and an opening that extends therethrough. The opening is defined by an inner surface that includes a threadform including a plurality of threads. The threads extend radially outward from the inner surface into the connector opening and include a first thread portion and an oblique cutback that extends through a portion of the threadform.
During assembly, the threaded component is rotated within the connector opening to initially engage the connector first thread portion and the cutback. As the threaded apparatus is torqued to be secured to the connector, the cutback facilitates less stresses being induced into the first thread portion. More specifically, because of the cutback, an amount of loading that may be transferred into the first thread portion is reduced in comparison to an amount of loading that may be induced into the first thread portion without the cutback. As a result, the cutback facilitates reducing a peak stress induced in both the male and female threads of the threaded component to more evenly transfer the loading through the connector threadform. As a result, an amount of stress induced into the connector threadform is facilitated to be reduced, thus extending a useful life of the connector.